1. Field of the Invention
The invention concerns a device for aligning fish conveyed head first regarding their plane of symmetry and for preparing the tail part of the fish for the aligned guiding during the handling of the fish in fish-processing machines, in particular fish whose cross-section approximates circular shape, the abdominal cavity of the fish having been opened by a strip cut extending at least behind the vent fin almost perpendicular to the plane of symmetry of the fish and equidistant to the seam of its belly, the device comprising conveying means for transporting the fish along processing tools of the processing machine, as well as a saddle-shaped guiding element which supports the fish in its abdominal cavity and defines a pair of support edges extending upwards symmetrically to the longitudinal axis or centre.
2. Description of Prior Art
In view of the ever-decreasing number of fish the need to supply human consumption with the highest possible yield grows. The consciousness about quality in the consumer of today means that such products made optimal in respect of yield must at least correspond to the usual quality standards. The prerequisite for reaching this goal in connection with fish-processing is that, especially with automatic bulk processing, processes and devices must be used which make a very precise handling possible. If a processing by cutting occurs, e.g. to produce fillets, then each fish must be guided and conveyed exactly aligned during the processing in order to make an economical cutting possible. This, however, is a special problem with fish having an almost circular cross-section since engaging fish by the outer contour, which engagement has an influence on the position of the plane of symmetry of the fish can only give an unsatisfactory result. This concerns especially the tail part which begins behind the end of the abdominal cavity and tends to twist because of the guiding and processing forces affecting the fish.
In practice there is known a device which is used especially as a supply aggregate in machines for the treatment of herring-type fish. The structure of that device comprises the features stated in the above introductory paragraph of this specification. It is possible with the help of this device to align fish whose cross-section clearly deviates from circular shape regarding their plane of symmetry sufficiently exactly, but it malfunctions on mackerel-like fish, for example, whose cross-section strongly approximates circular shape.
3. Object of the Invention
It is therefore the primary object of the present invention to universalise this known device in a manner that fish with almost circular cross-section can be so aligned and prepared that their further handling in exact alignment is possible.